Egg carton closer



March 17, 1959 w. G. ATKINSON 2,877,610

EGG CARTON CLOSER 3 Sheets-Sheet 1 Filed July 20. 1955 Inventor WILL/AM GERALD ATKINSON Y B -fd5id5w4yw Y Att'ys March 17, 1959 w. G.'ATKINSON 2,877,610

, EGG CARTON CLOSER Filed July 20, 1955 s Sheets-Shet 2 Inventor v WILL/AM GERALD ATKINSON BIY" March 17, 1959 w. G. ATKINSON 2,877,610

EGG CARTON CLOSER Filed July 20, 1955 s Sheets-Sheet s Inventor WILL/AM GERALD ATKINSON y Att'ys EGG CARTON CLOSER William Gerald Atkinson, London, Ontario, Canada, assignor to Somerville Limited, London, Ontario, Canada Application July 20, 1955, Serial No. 523,318

8 Claims. (CI. 53-38) This iiivention relates to amethod and means for folding cartons and in particular egg cartons.

The method of the invention and the inventive ap- 2,877,610 Patented Mar. 17, 1959 ce'pt' thepath of this elbow as the carton travels down theconveyor and force the elbow downwardly having the efiect of tucking the tuck-in flaps partly but not completely into position. Since the centre wall s travelling over the cut out portions in the centre partitions the tuck-in flap edges are guided into their correct position relative to the centre partition. When such partial insertion of the tuck-in flaps is achieved, side re-inforcing means for the side walls bounding the corn veyor path, ensure that the opposite elbows are in contact with each other and since the carton has then passed the end of the centre wall, the juxtaposed elbows then come paratus are ideally adapted for use with an egg carton provided with a centre partition and with side walls which extend upwardly to provide cover flaps and which cover flaps extend into a tuck-in flap for insertion downward into the egg carton adjacent the centre partitiom The two tuck-in flaps are preferably inserted in slots on one side of the centre partition and a cut out is made in the cross partitions of the carton leading to such slots. Thus the cut out portions in the successive centre partitions align along the length of the carton.

The method in accord with the invention comprises folding the cover and tuck-in flaps together inwardly relative to the side walls,-then folding the tuck-in flap inwardly and downwardly relative to the cover 'fiap whereby an upwardly projecting elbow is reproduced extending along the length of the carton and by downward pressure on the elbow accompanied by simultaneous guiding of the tuck-in flap edges inserting such tuck-in flaps partially but not completely into position adjacent the centre partition.

The closure of the carton includes tucking the leading edge of said tuck-in flaps a further distance into position by pressure downward on the leading edge of'theelbo'w, applying similar tucking pressure to the trailing edge of said elbow while allowing the middle portion of said into contact with a pivotally mounted idler cam wheel located above the carton path adapted to roll in contact with said pair of elb'ows from the beginning to the end of.-the carton as it passes beneath the cam. The pivot "radius of the cam is so designed that a greater radius exists intermediate the pivot point and the periphery atthat part of the periphery of the cam which contacts the egg carton at its leading and trailing edges so that .the added tucking of the leading and trailing edges of the tuck-in flaps is greater than the added tucking of said central insertion.

Reference may now be had to the attached drawings in which:

Figure 1 illustrates the overall closing apparatus. v Figures 2 to 4 illustrate the idler cam means and the method of making the final insertion of the tuck-in flaps in the carton.

Figures 5 and 6 illustrate an egg carton of the type with which the invention may be used. In Figure 1 a conveyor 10 is driven by drive means 12 through gearing 14. The gearing 14 simultaneously drives side belts 16 and 18 which provide lateral support and traction for the side Walls of the carton down the conveyor. I Leading on to the conveyor are guide walls 20 to ensure the passage of the carton longitudinally and in lateral alignment onto the conveyor.

Reference should now perhaps be made to the structure ofthe carton as it comes to the conveyor and in reference to Figures 5 and 6.

cover to bow upwardly between the respective pressures" on the leading and trailing edges.

It has been found that such a method results in egg cartons in which the tuck-in edges are, in general, more i even at'the forward and rearward edge of the carton" than they are by other closure methods and apparatus."

The structure for performing the closure in accordance with the invention, comprises a conveyor for conveying a carton longitudinally oriented, the conveyor' being accompanied by a centre guide wall located above Figures 5 and 6 illustrate the type of egg carton on which the closure in accord with the invention operates. The carton is provided with a central partition 30 which interlocks with a number of cross partitions 32. Each cross partition is slotted at 34 to receive the centre partition 30 and to receive tuck-in flaps 36 adjacent to such centre partition. The tuck-in flaps 36 are both received on one side of the centre partition and cut outs 38 are cut in the cross partitions to guide the tuck-in flaps 36 into place. Thus the notches 38 align throughout the length of the egg carton to provide in a sense a the carton path and of such a height and location as to enter into the longitudinally extending cut outs in the centre partition without interfering with the progress of the carton.

Progressively located along the conveyor path are the following folding and closure apparatus: that is, the travelling carton first encounters inwardly' sloping arms located in the path of the flap which have been caused to stand upwardly; such inwardly sloping arms acting to fold the cover and tuck-in flaps until the edge of the tuck-in flaps contacts the centre wall. With further surfaces outstanding from the centre wall interlongitudinally extending channel.

upwards into cover flaps 42 which in turn extend into the'tuck-in flaps 36 for insertion adjacent the centre partition. Score lines 44' and 45 respectively separate the'side walls 40 and the cover flaps 42 and the cover flaps 42 from the tuck-in flaps 36.

Referring again to Figure 1 it will be best to define the fact that the conveyor 10 is shown as travelling to the right in the drawing and that the conveyor path will be defined with reference to down the conveyor meaning toward the exist end for the carton and up the conveyor meaning toward the entrance end for the carton.

The carton guide plates at the entrance end have already been described and attached to these guide plates are twin rods 50 which slope inwardly, upwardly and forwardly over the conveyor path to contact the upstanding cover and tuck-in flaps and bend them together about seore line 44, whose projection in an upward direction I The egg carton is 7 provided with side Walls 40 which contiguously extend is ensured by the effect of the guide walls themselves. The conveyor path for the central portion of its length has located thereabove a substantially central wall 52 extending over the carton path down the conveyor the lower edge 54 of the wall 52 being of such a height thatfirst set of downwardly sloping guide surfaces 60 which,

are attached to the central wall 52 by downwardly sloping flanges 61 which serve as extensions for the central wall. The downwardly sloping surfaces 60 are adapted to intercept the upper edges of the carton tuck-in flaps 36 which with cover flaps 42 will have been bent in along score lines 44 to contact the downwardly extending flanges by the forwardly extending rods 50.

It Will be seen that the first set of downwardly sloping surfaces 60 act to fold the tuck-in flaps 36 relative to the cover flap 42 along the score line 45 and that between these two flaps is left an upwardly projecting elbow 62. Farther down the conveyor in the path of this up;

wardly projecting elbow 62 are surfaces 63 outstanding from the central wall and downwardly sloping adapted to intercept this upwardly projecting elbow and move it downwardly toward the carton proper. Meanwhile the edges ride downwardly along the centre wall 52 and since the centre wall projects into the cut outs 38, the tuck-in flap edges are guided into the slotting 34 adjacent the central partition 39 and the downwardly wedging force on the elbow 62 places these tuck-in flaps partially but not completely into position. Down the conveyor from the end of the second downwardly sloping surfaces 63 the central wall 52 terminates and thereafter the juxtaposed elbows 62 are forced into contact by the side belts 16 and unopposed by a central wall. While thus in contact they come into contact with an idler cam wheel 76 which is suspended above the conveyor path at such a height as to contact the twin elbows during the path of the carton therebeneath. The cam wheel 70 is preferably in the form of an eccentrically mounted circle and is freely rotatable upon its pivot so that the long radius between the pivot point and the periphery is gravitationally rotated downward in the absence of a carton passing therebeneath. The height of the idler wheel 70 is such that when a carton passes beneath, the long radius acts to insert the tuck-in flaps fully into position adjacent the central partition. Such insertion, however, results in rotation of the idler wheel 70 under frictional contact with the twin elbows 62 so that the wheel radius between contact and pivot becomes progressively shorter as the forward half of the carton passes therebeneath.

The periphery of the cam wheel 70 is so adjusted to the length of the carton that the cam wheel 70 makes. one complete rotation while the carton passes thereunder. Therefore at the middle of the carton the cam wheel 70 is contacting the elbows 62 with its minimum radius between pivot and contact while the maximum radius between contact and pivot occurs at the trailing edge of the carton. Thus the elbows 62 and the cover member are allowed to bow upwardly between the two ends of the carton and it has been found that the result of tucking said flaps to the maximum amount at each end of the carton but decreasing the amount of such tucking to a minimum at the centre of a carton therebetween has the effect of producing tuck-in .fiaps which are more in alignment than would be tuck-in flaps wherein a constant closing pressure was applied progressively along the whole carton length.

The operation of the closing means may now be re viewed. A carton with the cover flaps 42 extending upwardly from the side walls 40 encounters the guide walls 20 at the entrance to the conveyor which ensures that the cover flaps 42 with the tuck-in flaps 36 extending therefrom are extending vertically upward. The inwardly and upwardly extending rods 56 bend the cover flaps 42 inwardly until the upward edges of the tuck-in flaps 36 contact the downwardly extending flanges 61 of ;the first set of downwardly sloping surfaces 60. The

upper edges of the tuck-in flaps are thus brought into contact with the-downwardly sloping surfaces 61 which exert a folding effect along the score line 45 between tuck-in and cover flaps so that the tuck-in flap edges are now riding downwardly along the centre wall 52 and there are produced two upwardly extending elbows 62 between cover and tuck-in flaps. Meanwhile the lower edge 54 of the centre wall 52 is riding in the channel of cut outs 38 of the cross-partitions 32 just to one side of the central partition 30. The upwardly extendingelbows 62 then encounter the second downwardly sloping surfaces 63 which drive these elbows 62 downwardly until the tuck-in flaps 36 are almost but not quite in their final position in the carton. With the side belts 16 and 18 in contact with the side walls 40 the carton passes the end of the centre wall 52 andthe elbows 62 are brought into contact and provide at the edges of the cover flaps 42 a joint surface to contact the eccentric idler cam which exerts a maximum pressure on the leading edge of the joint surfaces decreasing to a minimum at the centre and increasing again to a maximum at the trailing edge. The action of this eccentric cam is to produce egg cartons in which the juxtaposed portions of the tuckin and cover flaps are relatively even.

The curvature of elbow 62 has been considerably exaggerated in Figures 3 and 4 for the purposes of'illustration. Therefore it will be understood that the curvature does exist but to a lesser degree.

I claim:

1. A method of closing egg cartons of the type having: side walls; cover and tuck-in flaps extending contiguously upwardly therefrom; cross partitions; and a centre partition with slotting in said cross partitions for receiving the tuck-in flaps adjacent thereto, comprising the successive steps of: folding the cover and tuck-in fiap together inwardly relative to the sidewall, folding the tuck-in flap in ward and downward relative to the cover, tucking said flaps partially but not completely into position adjacent the central partition, tucking the leading edges of said flaps a further distance into position adjacent said centre partition, tucking the trailing edges of said flaps a further distance into position adjacent said centre partition and allowing the middle portion of said flaps to bow upwardly between said tucked in edges.

2. Means for closing egg cartons of the type having: side walls; cover flaps extending contiguously upwardly from and separated by score lines from said side walls; tuck-in flaps extending contiguously upwardly from and separated by score lines from said cover flaps; a centre partition; cross partitions slotted to receive said tuck-in flaps adjacent their intersection with said centre partition; and cut outs in said cross partitions leading into said slots, said means comprising: a conveyor for conveying said carton; a centre wall located just above the central portion of said carton path adapted to ride in said cross partition cut outs and means progressively located along said path as follows: progressively inwardly sloping arms located in the path of said upstanding flaps adapted to fold the edgesof said flaps into contact with said centre wall; projecting plates outstanding from said centre wall downwardly sloping across the path of contact of. said flap edges with said wall adapted to bend said tuckin flaps downward relative to said cover, thus providing an upwardly extending elbow between said tuck-in flap and said cover flap; surfaces outstanding from said centre wall downwardly sloping across the path: of said elbow to exert a downward pressure thereon and to tuck said tuck-in flaps partially but not completely into said slots, side re-inforcing means bounding the path of said egg carton side walls to ensure the junction of said two elbows and a pivotally mounted idler cam wheel adapted to roll in contact with said cover flaps adjacent said elbows from the beginning to the end thereof, the pivot radius of said cam being so constructed that a greater radius exists intermediate the pivot point and the point of contact at the leading and trailing end of said carton than at the middle thereof.

3. A method of closing cartons having contiguous side walls and cover and tuck-in flaps comprising: folding the cover and tuck-in flap together inwardly relative to the side walls; folding the tuck-in flap inward and downward relative to the cover; tucking said flaps a certain distance into position adjacent said centre partition; further tucking said tuck-in flaps at their leading and trailing edges without corresponding tucking of the central portion of said flaps whereby the added tucking of said leading and trailing edges is greater than the tucking of said central 2o portion.

4. A method as claimed in claim 1 wherein the tucking of said leading edges is followed by the allowing of the middle portion of said flaps to extend upwardly and by the bowing of said central portion by the tucking of said trailing edges.

5. A method of closing egg cartons of the type having: side walls; cover and tuck-in flaps extending contiguously upwardly therefrom; cross partitions; and a centre partition with slotting in said cross partitions for receiving the tuck-in flaps adjacent thereto, comprising the successive steps of: folding the cover and tuck-in flap together inwardly relative to the sidewall, folding the tuckin flap inward and downward relative to the cover, tucking said flaps partially but not completely into position adjacent the central partition, and tucking said flaps to the maximum amount at each end of the carton but decreasing the amount of such tucking to a minimum at the centre of the carton.

6. Means for closing cartons of the type having contiguous cover and tuck-in flaps, comprising: means for inserting said tuck-in flaps partially but not completely into a carton and means for further tucking said tuck-in flaps to the maximum amount at each end of the carton but decreasing the amount of such tucking to a minimum at the centre of the carton.

7. Means for closing cartons of the type having contiguous cover and tuck-in flaps and having said tuck-in flaps partially but not completely inserted into said carton, whereby said carton has upstanding elbows at the junction of said cover and tuck-in flaps; comprising means for conveying said carton along a direction and a pivotally mounted idler wheel adapted to roll in contact with said elbows during travel of said carton in said direction, the pivot radius of said cam being so constructed that a greater radius exists intermediate the pivot point and the point of contact at the leading and trailing end of said carton than at the middle thereof.

8. Means as claimed in claim 7 wherein the centre of gravity of said cam wheel is on the side of, and aligned with, the greater radius.

References Cited in the tile of this patent UNITED STATES PATENTS 2,071,247 Benoit Feb. 16, 1937 2,091,426 Benoit Aug. 31, 1937 

